A search was launched last night after a man spotted a body floating in the sea off the Northumberland coast.
A man kayaking near South Beach in Blyth, Northumberland, rang the coastguard at about 6pm after he saw what appeared to be a body in the water opposite the Mermaid Cafe.
Police, coastguard, lifeboat crews and a rescue helicopter from RAF Boulmer were immediately scrambled, but no trace of a body was found despite an extensive search.
A Northumbria Police spokesman said last night the search would continue today, but it was not known whether there had been a body in the water or not.
He said: "The man saw what he believed to be a body floating in the water and rang the coastguard.
"We scrambled the police helicopter, which searched an extensive area and conducted numerous sweeps of the beach and water, alongside a rescue helicopter from RAF Boulmer, but nothing was found.
"There will be further searches at first light carried out by the coastguard alongside Blyth Volunteer Lifeboat.
"It is not known whether a body was in the water or whether the man saw something else such as a seal. But we are keeping an open mind."